I always make backups of my website before upgrading WordPress, but this time, I decided not to bother and sure enough, Murphy's law struck - it broke my website! This article explains how I fixed it without a backup. The process wasn't easy to find, so I hope this Step by Step helps you out.
The term "Backup" means the methods and processes involved to copy computer data (system data as well as application data) to media other than the ones where the data originally live (disk, tape, optical, cloud). "Restore" in turn means the methods and processes involved in data recovery, i. e., bringing back copied computer data to their original location. Backup/Restore primarily serves as a means of protection against data loss, be it due to disaster, corruption or sabotage. It can also be used for recovering data from an earlier point in time and even for cloning machines or applications. There is a wide variety of backup/restore software available, from expensive commercial products to free or open source tools.